About 15.5 million Iraqis had a chance to vote on the charter,
which lays out a democratic framework for a new Iraq but has
sharply divided the country on ethnic lines and was drafted only
after weeks of tortuous negotiations.

The charter requires a simple majority to be approved, but would
be rejected if two-thirds of the votes in at least three of Iraq's
18 provinces say no.

Results should be known within three days, chief electoral
official Adil al-Lami said.

"But if people have serious complaints, of course we will check
to see if they are justified. That would delay a final
declaration," he said.

Celebratory gunfire broke out in several Baghdad neighbourhoods
after polls closed, and senior electoral official Abdel Hindawi
said that according to a preliminary estimate, more than 61 per
cent of registered Iraqis cast ballots.

In Washington, US President George W Bush hailed the referendum
as "a critical step forward" in war-torn Iraq's move towards
democracy, whether or not the charter passed.

"By casting their ballots, the Iraqi people deal a severe blow
to the terrorists and send a clear message to the world: Iraqis
will decide the future of their country through peaceful elections,
not violent insurgency," he said.

Kurdish President Jalal Talabani had said after casting his
ballot inside Baghdad's heavily-protected Green Zone: "I think the
majority will vote yes."

In a second national vote since Saddam was toppled in April
2003, Iraqis were asked one question: "Do you approve the draft
constitution of Iraq?"

However, under a deal reached on Wednesday to try to bring
disaffected Sunni Arabs on board, voters decided on what is
effectively a partial constitution since politicians agreed that
amendments could be considered after new elections in December.

Many Sunnis, who make up about 20 per cent of Iraq's 26 million
population, fear federal provisions in the charter could lead to
the break-up of Iraq and leave control of its vast oil wealth in
the hands of the majority Shi'ites and the Kurds.

Saleh al-Motlaq, a Sunni spokesman for the National Council for
Dialogue who had helped draft the charter, said he had voted no
because he was not satisfied with the result.

"I took part in the consultation and I voted no to the
constitution," he said.

Despite a raft of security measures, including a ban on cars and
weapons and the closure of international borders, three Iraqi
soldiers were killed in a bomb blast as they inspected a polling
station north-east of the capital.

Two civilians were killed near Baquba, north-east of Baghdad,
when a homemade bomb targeted US forces who were guarding polling
boxes, local police said.

West of Baghdad, a civilian was shot dead during an attack on
police near a polling station. But generally, voting was peaceful
and turnout particularly heavy in the Kurdish north and southern
Shi'ite areas.

In the restive Al-Anbar province, however, 10 workers for the
Iraqi independent electoral commission were kidnapped by gunmen
while heading to the polls they were supposed to staff.

"Today we are in transition, we are about to attain political
stability built on a constitutional foundation," Shi'ite Prime
Minister Ibrahim Jaafari told reporters.

In Baghdad, dozens of men and women who came on foot to vote
entered polling stations in separate lines only after being checked
three times by police and US soldiers.

The constitution "represents hope for Iraq even if some things
are missing which will be addressed later," said Jamil Musawi, a
voter in the town of Kut, south of Baghdad.

The top UN envoy in Iraq, Ashraf Qazi, called the referendum "a
very important benchmark in the political transition" and stressed
that "whatever the choice of the Iraqis the political process will
proceed".

But underscoring hostility among Sunni Arabs, posters outside a
prominent mosque in Baghdad showed Iraq cut up by bloody sabres
held by hands attached to US and Iranian flags.

"No to the constitution that tears the unity of Iraq," it
declared.

In Hilla, south of Baghdad, loudspeakers at Shi'ite mosques
blared: "The constitution is Iraq's salvation," backing the
recommendation of Iraq's top Shi'ite cleric, Grand Ayatollah Ali
Sistani.

Security measures for the vote included a declaration of a
four-day national holiday that began on Thursday, an extended
curfew, a ban on civilians carrying weapons and a ban on the use of
personal vehicles.

International borders were closed to traffic except for the
transport of food, water and fuel. Baghdad airport is shut down
until Monday.

The US ambassador to Iraq, Zalmay Khalilzad, said if the
democratic process advanced and if enough Iraq security forces
could be trained, the US military presence could begin to decrease
next year.